660 



Kamerlingh Onnes and Bhaak and 7'= 90°. 12 K bj Henning. '). 



In Table II the results of Kamerlingh Onnes and Braak and those 

 of V. Siemens, the latter after tfie reduction of his temperature- 

 measurements to those of Kamerlingh Onnes and his collaborators 

 has been corrected according to Holst*), are compared with the 

 formula which represents my observations'). 



The results show that except for the lowest points Holst's reduction 

 of V. Siemens' observations has been very successful. 



The results for nitrogen are given in Table III. 



1) Ann. d. Phys. (4) 40 (1913) p. 635. The theoretical correction to the readings 

 on the scale of the hydrogen-thermometer given by Berthelot which Henning 

 applies, does not differ appreciably in this region of low temperatures from the 

 experimental correction found by Kamerlingh Onnes and Braak. All the same it 

 is doubtful whether Henning's value may be looked upon as a final confirmation 

 of the boiling point found by Kamerlingh Onnes and Braak, since his measure- 

 ment contains an uncertainly to which attention was drawn in note 1 to p. 998 

 of these Proc. XX (2) (Comm. N^. 152a). 



') In this correction Holst puts the temperatures at the higher points 0.02 and at 

 the lowest point 0.01 of a degree higher than Kamerlingh Onnes and Bbaak, which 

 is due to the fact that in the reduction he uses his own formula of inteipolation 

 instead of the observations themselves. This explains the difference of the deviations 

 at the top of the two columns for coinciding points, although v. Siemens in liis 

 determinations talces those of Kameelingh Onnes and Braak as his starting point. 



') As observed in Comm. W. 107a, there is a systematic difference of 0.10 degree 

 at the boiling point and 0.13 degree at the lower points between the observations 



